When I was pre-registering, I also bought a Formal Ball ticket, though I noticed that there were two options, one that said "5pm - 9pm" and another that said "7pm - 9pm".

Is this a typo? I bought the 5pm - 9pm one just to be sure; it just seemed a bit odd that one choice was for 4 hours and the other was for 2 hours, despite being the same price.

Also, where do I pick up this ticket? Same place as badge pickup, or somewhere else?

Also also, the apparel that I'll be using is a cosplay, but it's practically just a standard business suit (pants + jacket + dress shirt) with regular black dress shoes. Will that be okay? I've worn it to similar "formal ball" events at other conventions.